The present invention generally relates to devices for warning a driver of a vehicle of potentially dangerous situations involving the ability of the driver to operate the vehicle and, more particularly, to an improved device for detecting symptoms of, and warning the driver of, the onset of fatigue or drowsiness.
Accidents commonly happen as the result of driver inattention resulting from fatigue or drowsiness. A majority of automobile accidents caused by such fatigue or drowsiness are automobile (motor vehicle) collisions on interstate or other highways where, for example, monotonous road and scenery conditions promote xe2x80x9chighway hypnotismxe2x80x9d and attendant driver fatigue and/or drowsiness.
Devices have been developed which sound an alarm to alert the driver when the driver has dozed off but which do not test the current driving ability of the driver and thus are of limited value in many potentially dangerous situations. Other devices do test the driver but suffer other shortcomings. The latter category includes devices such as those described in U.S. Pat. Nos. 5,684,455 to Williams et al and 5,402,108 to Tabin et al. The Williams et al patent discloses a driver alerting device comprising green, yellow and red indicator lights, a timer, a resetting mechanism and an audible alarm. The driver is required to reset the device after the illumination of the green light. If the device is not reset before a first timed period has elapsed, the yellow light then illuminates and flashes for a second timed period. If the device is not reset before the second timed period has elapsed, the red light then illuminates and flashes, and the audible alarm sounds until the device is reset. The Tabin et al patent discloses a driver alerting device including a red indicator light, a timer, a resetting mechanism and an audible alarm. The driver is required to reset the device within a timed period after the red indicator light illuminates and begins flashing. If the driver does not reset the device before the timed period has elapsed, the audible alarm then sounds.
In accordance with the invention, a driver fatigue detector is provided which tests a driver for the onset of fatigue and/or drowsiness and, more particularly, in accordance with an important aspect of the invention, tests the driver as to whether the eyes of the driver are properly focussed on the road ahead. The device of the invention interrupts periods of fatigue or drowsiness by causing the driver to respond or be warned. The invention will reduce or eliminate accidents attributable to the phenomenon of xe2x80x9chighway hypnotismxe2x80x9d described above, will reduce such accidents such as rear-end collisions and potentially dangerous situations occurring in the traffic lane and on the side of the road, running off the road, crossing the center line or median, sideswiping moving or parked vehicles, running red lights or stop signs, loss of control or rollovers due to evasive maneuvers, and rollovers or like accidents at exit ramps caused by fast last minute turns caused by the inattention of the driver in noting a desired exit in time to slow down. As discussed in more detail below, the ability of the device of the invention to test whether the eyes of the driver are properly directed to the road ahead is a major advantage over prior art devices of the same general type.
According to the invention, a device is provided for alerting a driver of an automotive vehicle as to the onset of fatigue, characterized by eyelid droop, head droop and a like condition wherein the eyes of a driver are not directed straight ahead onto the road, the device comprising: a housing or case adapted to be affixed to a portion of the automotive vehicle so as to be located at the upper periphery of the field of vision of the driver, the housing comprising: an indicator lamp viewable by the driver in the upper periphery of the field of vision of the driver, an electrical control circuit for controlling illumination of said indicator lamp so as to provide illumination thereof after passage of a predetermined time interval, a driver controlled reset switch for providing resetting of said time interval upon depression of the reset switch by the driver, and alarm means for producing an alarm signal when the indicator lamp has been illuminated after the passage of said predetermined time interval and one reset switch has not been depressed after passage of a further predetermined time period.
Preferably, the housing further comprises a driver controlled pushbutton controller connected to the control circuit for providing initial energization of said indicator lamp.
Advantageously, the housing includes affixing means for affixing the housing to a sun visor of the vehicle. The affixing means preferably comprises a spring clip secured to the housing and adapted to clip onto the sun visor.
In a beneficial implementation, the housing further comprises a mounting member extending outwardly from the housing for mounting the indicator lamp so as to face the driver when the housing is affixed to the sun visor or otherwise disposed in an upper peripheral portion of the field of view of the driver. The indicator lamp preferably comprises a light emitting diode. Advantageously, the indicator lamp comprises a red light element.
The housing preferably further comprises an interior compartment including, housed therein, a circuit board containing the control circuit.
The electrical control circuit preferably includes a counter circuit for counting the number of times that the indicator lamp has been illuminated.
Advantageously, the housing further comprises a master reset switch for resetting the predetermined time interval to a different, longer duration interval.
In a beneficial embodiment, the housing includes a battery storage area for storing batteries for supplying power to said control circuit. Alternatively, or in addition, the housing preferably includes a connector for connecting the control circuit to an external electrical power source such as the cigarette lighter of the vehicle.
The alarm means preferably includes an alarm and an alarm control, forming a part of said electrical control circuit, for controlling actuation of the alarm such that the alarm is activated if the reset switch is not actuated after said indicator lamp has been illuminated. Advantageously, the electrical control circuit includes means for monitoring said alarm control circuit and for turning said electrical control circuit off if said alarm control circuit is not reset after the passage of a further predetermined time interval (e.g., a few minutes) in order to save power.
Further features and advantages of the present invention will be set forth in, or apparent from, the detailed description of preferred embodiments thereof which follows.